Azo dyestuffs



United States Patent C) 3,193,546 AZO DYESTUFIFS Harlan B. Freyermutli, Easton, Pa, David I. Randall, New Vernon, Ni, and Eeaui R. Hue, deceased, late of Easton, Pa., by Dolores M. Buc, administratrix, Easton, Pin, assignors to General Aniline 8; Film Corporation, New York, N.Y., a corporation of Deiaware No Drawing. Filed Dec, 28, 1961, Ser. No. 164,210

4 Ciaiins. (Cl. 269-200) This invention relates to a novel group of azo dyestuffs, and more particularly to novel azo dyestuffs and their use for dyeing polyamide fibers.

In the production of nylon fabric, the variation of tension of the warp in woven goods and variations in tension of knitting machines result in an increase in the number of crystalline regions in the nylon. Most acid wool dyes do not penetrate these crystalline regions in the nylon sufficiently during the dyeing operation to produce even or level dyeings. The resulting objectionable barr effects are also thought to be partially due to variations in the temperature of heat setting of the nylon goods It is an object of this invention to provide novel dyestuffs which will not be subject to the above disadvantages. Another object of this invention is the provision of novel azo dyestuffs which can be used for dyeing nylon and other polyamide fibers from an acidic aqueous medium to produce dyeings exhibiting little or no barr and other objectionable effects. Still another object of this invention is the provision of a process for producing polyamide dyeings exhibiting little or no barr effects and having improved fastness to washing, and alkaline and acid perspiration. Other objects and advantages will appear as the description proceeds.

The attainment of the above objects is made possible in accordance with this invention by the provision of azo dyestuffs having the formula:

ornsoionionzov (in X wherein Y is selected from the group consisting of H and M, R is selected from the group consisting of H, lower alkyl and lower alkoxy, X is selected from the group consisting of H and halogen, and M is selected from the group consisting of H, metal, ammonium, and amine cations. It has been found that these dyestufis can be applied to polyamide fibers from an acidic aqueous medium to produce level orange dyeings exhibiting little or no barr effects and having good to excellent fastness to washing and/or to alkaline and/ or acid perspiration.

In the above formula, X may represent H, Cl, Br, F, or I, R may represent H, methyl, ethyl, methoxy, ethoxy or the like, and M may represent H, metal (including alkali metal and alkaline earth metal) such as sodium, potassium, lithium, calcium, magnesium, strontium, barium, and aluminum, ammonium, or amine such as mono, di-, and tri-methylamine, -ethylamine, -propylamine, -ethanolamine, and -propanolamine, pyridinyl, and morpholinyl, and the like. M is preferably alkali metal, particularly sodium and the CH SO CH CH OY group is preferably in meta positionrelative to the azo The above defined dyestuffs may be readily prepared by coupling a suitable fi-naphthol sulfonic acid in known manner with a diazotized aminobenzylsulfonylethanol of the formula:

wherein R has the values given above and the methylenesulfonylethanol group is preferably in meta position relative to the amino group, followed by sulfation of the OH in said group. These diazo components may for example be prepared by chloromethylation of a suitable substituted or unsubstituted nitrobenzene (as by reaction with bis-chloromethyl ether in sulfuric acid), reaction of the resulting chloromethylated nitrobenzene with mercaptoethanol, oxidation of the resulting nitrobenzylthioethanol to the corresponding nitrobenzylsulfonylethanol (for example, by reaction with hydrogen peroxide in the presence of a tungstic acid catalyst as dis closed in US. 3,006,963), and reduction of the nitro group to amino (for example, by treatment with iron or the like in sulfuric acid or the like). The preferred diazo components containing the methylenesulfonylethanol group in meta position relative to the amino group, and methods for their production, are disclosed and claimed in the copending application of Buc et al., Serial No. 858,034 filed December 8, 1959, now U.S. Patent No. 3,094,516. As examples of suitable diazo components, there may be mentioned 2(2-rnethoxy-5- aminobenzylsulfonyl)ethanol of the formula:

OCHa

CH SOZCH CH OH V LITE:

2(Z-methyl-S-aminobenzylsulfonyl)ethanol, 2(2 ethoxy- S-aminobenzylsulfonyl)ethanol, 2(4-methoxy 5 aminobenzylsulfonyl) ethanol, 2(4 ethyl 5 aminobenzylsulfony1)ethanol, 2(3 aminobenzylsulfonyl)ethanol, 2(4- arnin obenzylsulfonyl ethanol, 2 2-rnethoxy-4-aminobenzylsulfonyl)ethanol, 2(2 ethyl-4-aminobenzylsulfonyl) ethanol, and the like.

, As examples of suitable coupling components for reaction with the above described diazo components, there may be mentioned Z-naphthol-S-sulfonic acid, Z-naphthol-5-, -6 or -7-sulfonic acid, 5-chloro-2-naphthol-8- cate optional substitution in any unsubstituted nuclear position.

sulfonic acid, and other halo-substituted Z-naphtholsulfonic acids and the like.

It will be understood that in the production of the dyestuffs of this invention wherein Y is H, a subsequent sulfation of the OH group in the above described diazo components is omitted. On the other hand, dyestuffs of this invention wherein Y is $0 M may also be prepared by first sulfating the OH group of thedescribed diazo component followed by diazotization thereof and coupling with the described naphthol coupling component. This expedient of preliminary sulfation of the diazo component has certain advantages in that the amount of sulfating agent required is reduced, the water solubility of the diazo component is thereby improved, etc. Any usual sulfating agent may be employed, sulfuric acid being preferred.

The above defined dyestuffs of this invention are useful for dyeing (including printing) polyamide fibers from an acidic aqueous medium, which latter term is intended to include solutions, disperions, or stable or colloidal suspensions of the dyestufi adjusted to an acid pH and appropriately thickened in known manner when employed for printing. The aqueous medium may be applied by jig dyeing, padding, spraying, printing or other suitable manner. A weakly acid medium is preferred, the pH generally ranging from about 3.5 to less than 7. Any acid may be employed for adjustment of the pH, as for example formic, acetic, sulfuric, and the like; The temperature of application should range from about 140 F. up to the boiling point of the medium although higher temperatures maybe employed when using a thermal V dyeing process involving a subseqeunt curing step;

The dyestutfs of this invention are applicable for 'the dyeing of any of the synthetic linear condensation superpolyamide fibers suchas nylon, Perlon, Silon, Steelon, Furon, and the like. For example, the nylon may be derived from adipic acid: and hexamethylenediamine (nylon 66), omega-aminocaproic acid (nylon 6), sebacic acid and hexamethylenediamine (nylon 610), or mixtures or copolymers thereof. The polyamide fiber derived from polypyrrolidcne may likewise be dyed by the present process; Natural protein fibers such as silk, goat and other animal hair, and particularly wool are readily dyed by the processof the present invention. Artificial regenerated protein fibers such as derived from casein, zein, or soya bean or the like may also be dyed by the'present process. Such regenerated protein fibers are'preferably ofthe hardened type as obtained for example by acetylation or treatment with formaldehyde.

Optimum results are obtained when the dyestuffs of at the defined elevated temperatures to woven or knitted fabrics having a basis of nylon since by this method the described barr effects are minimized. The dyestuffs of this invention are substantive to the polyamide and ac v 60 g; sodium chloride. The dye mixture was filtered and the cake was slurried in r 150 mlaof water. The residual acid was neutralized by the gradual addition of 7.8 g. sodium bicarbonate to pH 7.2., A few drops of glacial acetic acid was added to reduce'the pH to 6.5. The dyestutf was precipitated by addition of g. N aCl and stirred for several hours, filtered and dried in a vacuum oven at 85 C.;

' Yield 12.09 g. The dye'stufi has the formula:

' this invention are applied from an acidic aqueous bath cordingly the fibers should be allowed to remain in the a dye bath until the 'd'yestuflf is substantially completely exhausted. T

Preferably, the dyeing process is carried out without addition of 'acid as described above until most of the dyestuif has exhausted on to the fibrous'rnaterial in order to promote levelnessof the dyeing. Subsequent addition of acid aids in obtaining complete exhaustion of the dyestutf on the fiber Whereafter the'dyeings are 1 simply rinsed with water and dried.

cooled to. 0-5 C. and diazotized by gradually adding 7 with stirring L 72 ml. 10% wt./vol. sodium nitrite solution, maintaining the temperature at 0-5 C. Stirring at 0--5 C. .was continued for 10 minutes after the addition of nitrite solution was complete. 7 (potassium starch-iodide paper test) was destroyed by the gradual addition of V 14 ml. 10% wt./vol. sulfonic acid solution. The diazo solution was made up to 400 ml. volume with waterand one-fourth of this diazo solution (0.025 mole) was used in the coupling reaction. a (b) Coupling reaction. 1

12.7 g..2-naphthol-8-sulfonic acid, 46.3% (0.025 mole plus 5% excess) wasdissolved in 100 ml. water by the addition of 25 ml. 20% wt./vol. sodium carbonate'solution and (a) above. was added. After coupling was completed,-

the dyestuff was precipitated by the gradual addition of r The excess nitrous acid ((1) Dyeing.--0.1 g. of the dyestufl? of (c) above is added to .300 ml. water and the mixture is heated to 140 F. 10 g. nylon piece goods is added to thedye bath and manipulated while the temperature is increased to the boil and held at this temperature for one. hour. 1% formic acid (based on the volume of the bath) is added and the bath is held at the boil until the dyestuff is exhausted onto the nylon. The nylon piece goods is removed and rinsed with cold water. i

The nylon is dyed a bright orange shade having excellent wash fastness (wash test No. 3, AATCC) and alkaline and acid perspiration. The dyeing is level and free of barrefiiects.

This invention has be'en disclosed with respect to certain preferred embodiments and various modifications and variations thereof will become obvious to the person skilled in the art. It is to be understood that such modications and variations are to be included within the spirit and scope of this invention. r

We claim: i

1. An azo dyestuif of the formula:

on sozornonioY on group is in one of the meta and para positions relative to the azo bridge. I p

2. A gdyestutf as defined in claim 1 wherein the CH SO CH CH OY group is in meta position relative to t e azo bridge, Y is M, R is lower alkoxy, X is H, and M is alkalimetal.

3. A dyestuff as defined in claim 1 wherein the CH SO CH CH OY group is in meta position'relative to the azo bridge, Y is H,- R islower alkoxy, X is H, and M is alkali metal. w

4. An 2120 dyestuir of the formula:

CHzSOzCHgCHgOSOaNa OH References Cited by the Examiner UNITED STATES PATENTS 6 Heyna et a1. 260-200 Wenker 260-200 Brassel et a1. 8-42 Buc 260-380 XR Randall 260-163 FOREIGN PATENTS France.

OTHER REFERENCES Luttringhaus, H., American Dyestufr Reporter, v01. 50, April 3, 1961, pp. 3035.

CHARLES B. PARKER, Primary Examiner. 

